A.O. Smith 404 - Manuals

5 At times you may not be able to smell an LP gas leak. One causeis odor fade, which is a loss of the chemical odorant that gives LPgas its distinctive smell. Another cause can be your physicalcondition, such as having a cold or diminishing sense of smell withage. For these reasons, the use of a pro...

6 DIFFERENTIAL PRESSURE SWITCH The differential pressure switch ensures that a sufficient differentialexists between the air pressure in the pre-mix chamber and the inletof the burner for safe, combustion and proper low NOx emission. Theswitch has two pressure taps marked "+" (positive) and ...

7 DRAIN VALVE (Not Supplied) Additional drain valves must be obtained and installed on each boilerand tank for draining purposes. SAFETY RELIEF VALVES Your local code authority may have other specific relief valverequirements not covered below. WARNING THE PURPOSE OF A SAFETY RELIEF VALVE IS TO AVOI...

8 the authority having jurisdiction, must be provided with a low watercutoff device either as a part of the boiler or at the time of boilerinstallation. WARNING UNDER NO CIRCUMSTANCES SHOULD THE EQUIPMENT ROOMWHERE THE BOILER IS INSTALLED EVER BE UNDER NEGATIVEPRESSURE. PARTICULAR CARE MUST BE TAKEN...

9 SEE FIGURE 6). AT LEAST TYPE B VENTING MUST BE USEDWITH THE STANDARD VENTING OPTION (thru-the-roof) USINGTHE NATIONAL FUEL GAS CODE VENT TABLES. TYPE B VENTP I P E C A N N O T B E U S E D I F T H E B O I L E R I S V E N T E DH O R I Z O N TA L LY O R A S A D I R E C T V E N T ( S E E PA G E S 1 2T...

10 POWER VENT (OPTIONAL) The length of vent used in horizontally vented installations can beextended beyond the lengths shown in Tables 11 and 13 byimplementing the kits listed below: TABLE 9: POWER VENT KITS. CONNECTING BOILER TO A COMMON VENT Do not connect the boiler to a common vent or chimney w...

11 Figure 5. Vent Termination Installation Clearances CAUTION DIRECT VENTING INTO DEAD AIR SPACESSUCH AS ALLEYS, ATRIUMS AND INSIDECORNERS CAN CAUSE RECIRCULATION OFFLUE GASES. RECIRCULATION OF FLUEGASES WILL CAUSE SOOTING, PREMATUREFAILURE OF THE HEAT EXCHANGER ANDICING OF THE COMBUSTION AIR INTAKE...

12 STANDARD VENT - VERTICAL (CATEGORY I) IMPORTANT! VENT PRESSURE MUST BE MAINTAINED BETWEEN -0.02" W.C. AND -0.04" W.C. AT 24" (61.0 cm) ABOVE BOILER COLLAR. • Connection for the appliance exhaust vent to the stack must be as direct as possible. Maximum and minimum venting lengthfor Cat...

15 DIRECT VENT - HORIZONTAL (CATEGORY III) WARNING: No substitutions of flue pipe or vent cap material are allowed. Such substitutions would jeopardize the safety and health of inhabitants. • A maximum of two elbows can be used on inlet and outlet vent piping respectively. Each elbow is equal to 10 ...

16 HYDRONIC INSTALLATION The following is a brief description of the equipment required forinstallations noted in Figure 10. All installations must comply withlocal codes. TABLE 14: INSTALLATION ITEMS NO. SUGGESTED ITEMS FOR INSTALLATION 1. PAIR OF SHORT PIPE NIPPLES, PAIR OF BOILERLOOP TEES AND BAL...

17 Large systems with multiple boilers should include main watertemperature controls (with or without outdoor reset) to sequence theboiler on and off, in relation to the load on the system. 24 VAC System Controller (Optional) GB models require a field supplied 24VAC operating control to beinstalled ...

18 related to approximate water volume of the system. The systemshould be turned on to circulate water mix for about one hour andthen flush clean with fresh water. Before operating the boiler, the entire system must be filled withwater, purged of air and checked for leaks. Do not use Stop Leak oroth...

19 ONE GENESIS (MODEL GW) HOT WATER SUPPLY BOILER WITH HORIZONTAL TANK Figure 12. Tank probe installation. PRESSURE RELIEF VALVE RATING SHOULDNOT EXCEED PRESSURE CAPACITY OF ANYCOMPONENT IN THE SYSTEM. PIPING SHOULD CONFORM TO LOCAL CODES. BALL VALVES ARE SHOWN FOR SERVICINGB O I L E R . H O W E V E...

20 ONE GENESIS (MODEL GW) HOT WATER SUPPLY BOILER WITH VERTICAL TANK Figure 13. Single boiler with vertical tank. PRESSURE RELIEF VALVE RATING SHOULD NOT EXCEED PRESSURE CAPACITY OF ANY COMPONENT IN THE SYSTEM. PIPING SHOULD CONFORM TO LOCAL CODES. BALL VALVES ARE SHOWN FOR SERVICING BOILER. HOWEVER...

21 T ABLE 15. Suggested Pipe Size For Multiple Gas Appliances (Natural) T ABLE 16. Suggested Pipe Size For Multiple Gas Appliances (Prop ane Gas) Length of Pipe in Feet (Metres) Maximum Cap acity of Pipe in BTU/hr and kW for Gas Pressures of 14 in. W .C. (0.5 p si) or Less and a Pressure Drop of 0.5...

22 Where it is necessary to use more than the average number ofpipe fittings i.e. elbows, tees, and valves in gas supply line, usea p i p e l a r g e r t h a n s p e c i f i e d t o c o m p e n s a t e f o r i n c r e a s e dpressure drop. Gas control trains are unique for each Genesis II unit. Stag...

23 GB/GW 2100 GB/GW 2500 GB/GW 1000 - 1500 GAS MANIFOLD ASSEMBLY GB/GW 1850 Figure 14. GB/GW 1000 - 2500 Gas Manifold Assembly Diagrams.

26 GENESIS GB/GW 1000-2500 SERIES 400 SCHEMA TIC DIAGRAM FIGURE 16.

31 Fuse Protection The 24VAC circuitry is protected with a 3 amp fuse on the FlameControl Boards (FCB) and a 7.5 amp fuse on the Central ControlBoard. If the fuse opens, a red LED located near the fuse will light.See Figures 17 and 18. If the red LED is illuminated, replace thefuse. Repeated failure...

32 Lighting Instructions for the G(B/W) 1000 through 2500 models A. THIS APPLIANCE DOES NOT HAVE A PILOT. IT IS E Q U I P P E D W I T H A N I G N I T I O N D E V I C E W H I C HAUTOMATICALLY LIGHTS THE BURNER. DO NOT TRY TOLIGHT THE BURNER BY HAND. B. BEFORE OPERATING: SMELL ALL AROUND THE APPLI- AN...

34 TABLE 20. RISK OF SCALDS. TEMPERATURE TIME TO PRODUCE 2nd & 3rd SETTING DEGREE BURNS ON ADULT SKIN OVER 170°F (77°C) NEARLY INSTANTANEOUS 160°F (71°C) ABOUT 1/2 SECOND 150°F (66°C) ABOUT 1-1/2 SECONDS 140°F (60°C) LESS THAN 5 SECONDS 130°F (54°C) ABOUT 30 SECONDS 120°F (49°C) OR LESS MORE THA...

36 CCB - Three position Dipswitch (Flame Control Section) SW2:This dipswitch is similar to the FCB dipswitches described below, but with only three switches being used: the number of blowerspeeds (switch #3), Hi Gas option (switch #2) and a spare (switch #1). Only the blower speed and Hi Gas options...

37 Operating Sequence NOTE: The following sequence is based on a three-stage system. 1. The EMC 5000 controller has four modes of operation: Initialization,Standby, Running, and Service. The internal CCB and FCB microscontrol these modes through a sequence of steps (or States) whichare further descr...

38 followed by 15-second inter-purge period, then the systemreturns to step 7, if the "Trial for Ignition" dipswitch is set forthree (3) tries. If the dipswitch is set for one (1) trial, the systemwill declare an error and boiler will require resetting the control. 10. If a flame is detected...

39 • Menu Screen: Displayed when the user presses the "Menu" key. This screen isthe selection point for the other 9 screens. • Temperature Screen: Displays the sensed temperatures of the Outlet, Inlet, and Tankprobes. Also displayed is the calculated Delta T (Outlet minusInlet) for the syste...

40 • Soft Fault State: (See "Fault Description" section for list of softand Auto Reset faults.) The CCB turns off the Powered Vent and the IRI Gas. The pumpremains on for the selected post-circulate time to cycle the hotwater out of the boiler. The FCB's are commanded to shut downand the Ala...

41 6. Use the UP or DOWN key to select the value you wish to enter. 7. Touch the SELECT key to accept and store the new value. • Operating Differential Setpoints:E a c h o f t h e t w o s t a g e s h a s a n i n d e p e n d e n t O p e r a t i n gDifferential setpoint. OPERATING DIFFERENTIAL SETPOIN...

42 when an error is detected. It will also go to this screen uponpower-up if an error was still valid when power was turned off. NOTE: Errors are cleared from this screen by pressing the"select" key. • Error History Screen: This screen displays a list of the last 9 errors (with time stamps)t...

44 PREVENTATIVE MAINTENANCE This is an induced burner and the flame is not supposed to be directlyon the burner. The flame should be just above the burner deckapproximately 1/8” and blue in color. See Figure 22. Visually check flame characteristics through the view port locatedunder the left-hand he...

45 After placing the boiler in operation, check the ignition system safetyshut-off devices for proper operation. To accomplish this with themain burners operating, close the valve on the manifold. Withinfour seconds the main burners should extinguish. If this does notoccur immediately, discontinue g...

46 all of the hardness (lime). For this reason it is recommended that aregular schedule for deliming be maintained. The time between cleaning will vary from two to six monthsd e p e n d i n g u p o n w a t e r c o n d i t i o n s a n d u s a g e . A c h a n g e o fapproximately 5 o F (3°C) in the no...

47 NEW BOILER LIMITED WARRANTY A. O. Smith Corporation, the warrantor, extends the following LIMITED WARRANTY to the owner of this hydronic boiler: 1. If within TEN years after initial installation of the boiler, the heat exchanger shall prove upon examination by the warrantor to be defective in mat...